Dynamic control of super- and subradiance of quantum emitters via near-field photonics and time-varying media

Achieving dynamic and broadband control of superradiance and subradiance at elevated temperatures is central to quantum photonic technologies. Herein, we theoretically investigate near-field photonics combined with adiabatic and non-adiabatic time-varying media—created via temporal modulation of material properties—to dynamically generate and coherently manipulate quantum emission states, including single photons and photon pairs. Distinctively, this cavity-free near-field method operates effectively at practical temperatures (tens of Kelvin), circumventing traditional operational constraints. We initiate this approach by exploiting plasmonically coupled silicon carbide color centers, which are used as quantum emitters (QEs), with relatively long coherence lifetimes, enabling precise quantum state control before temperature-induced dephasing sets in. In particular, a hybrid plasmonic waveguide is used as the light delivery method, where its subdiffracted near-field generates nanoscale heating that effectively tunes the energies of color centers, via phonon occupation, on resonance with the near-field. Furthermore, we employ transparent conducting oxides, such as indium tin oxide, that may achieve significant refractive index modulation on the femto–picosecond timescales. The resulting behavior is that of a photonic time crystal (PTC) or an epsilon-near-zero (ENZ) material response, dependent on modulation times, and characterized by the amplification or increased absorption of light, respectively, where both enhance field localization around the embedded QEs and extend periods of super- or subradiance compared to static conditions. Our methodology significantly simplifies scalable quantum photonic integration, while advancing quantum memories and entanglement capabilities under accessible conditions.